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Phrao fire, 14 April 2026 พร้าว · Phrao

Out · last detection 16 Apr 2026, 20:04 UTC

The fire started on 14 April 2026 in Phrao, Thailand, and satellites saw it burning for 5 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,215 hectares from heat detections, spread across a single municipality.

It is the 282th largest in Chiang Mai Province since 2016 (of 399 with a page). Number 532 in Thailand in 2026, of 689.

The power measured by the satellite is low (3.1 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Compare with…
Burnt area
1,215ha
GWIS perimeter (Copernicus)
Duration
5days
14 Apr 2026 – 18 Apr 2026
Municipalities hit
1
districts
Started on
14 Apr
2026
Heat detections
10
in a single hotspot: 3 MW
Danger at start
30
High · FWI index
Average daily power
6MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 14 Apr18 Apr
16 Apr 2026

How it evolved, day by day

14 Apr 2026 · 4 MW · 3 15 Apr 2026 · 12 MW · 6 16 Apr 2026 · 2 MW · 1
14 Apr 15 Apr 16 Apr

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

36°high
36km/h · peak gust
29%lowest humidity

It had gone 30 days without rain (1 mm or more) when it started. Rain came after the fire: 5.9 mm on 25 Apr.

This area had burned before

50% of the perimeter overlaps earlier fires recorded since 2016: 269 ha in 2016, 401 ha in 2017, 65 ha in 2020, 258 ha in 2023, 152 ha in 2025. Part of it burned more than once, so the yearly figures add up to more than the 604 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 0.8% of the area of London (12 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. Phrao พร้าว where it started
    1,223 ha reached on 14 Apr
    1.0 %

Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance runs from the point marking the centre of each area to the nearest fire: staying a kilometre away does not mean it reached the houses.

People and buildings inside the perimeter

GHSL 2025
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2025, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned. The GHSL 2025 epoch is a projection made from 2020 and earlier data.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

The weather day by day

ECMWF ERA5 reanalysis at the fire location, the standard reference for past weather, and the Canadian Fire Weather Index (the same system Copernicus uses), computed by WorldFires from that data. Days after the fire run until the first rain.

Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

Day High Min. humidity Peak gust Rain Danger (FWI)
14 Apr 35.1 °C 32 % 30 km/h 0.0 mm High 30
15 Apr 35.9 °C 29 % 36 km/h 0.0 mm High 33
16 Apr 34.7 °C 33 % 27 km/h 0.0 mm High 30
17 Apr 34.3 °C 35 % 25 km/h 0.0 mm High 30
18 Apr 34.2 °C 38 % 28 km/h 0.0 mm High 30
19 Apr after 34.0 °C 36 % 37 km/h 0.0 mm High 32
20 Apr after 33.5 °C 40 % 33 km/h 0.0 mm High 28
21 Apr after 34.8 °C 40 % 31 km/h 0.0 mm High 29
22 Apr after 35.9 °C 35 % 28 km/h 0.0 mm High 29
23 Apr after 32.5 °C 46 % 26 km/h 0.0 mm High 26
24 Apr after 35.0 °C 36 % 26 km/h 0.1 mm High 26
25 Apr after 29.9 °C 61 % 33 km/h 5.9 mm Very low 4

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

Before · 7 Apr 2026
After · 25 Apr 2026

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

The smoke

CAMS · Copernicus

On 17 April 2026 the air beside the fire reached 175 µg/m³ of PM2.5. That day averaged 91: 6.1 times the WHO daily guideline (15).

PM2.5 peak175 µg/m³
Days over the guideline9 days
PM10203 µg/m³
Optical depth1.80
121314151617181920
Good Fair Moderate Poor Very poor Extremely poor

Particles from the Copernicus CAMS model at the centre of the perimeter; these are not measurements in each town. The pale bar is the worst hour, the solid one the daily average.

Open-Meteo.com (CC BY 4.0) · Copernicus Atmosphere Monitoring Service (CAMS)

Detections table · 10Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
Date and timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Thailand ›

Frequently asked questions

How long did the Phrao fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 14 April 2026 to 18 April 2026 (5 days). The perimeter dates it from 14 April 2026 to 17 April 2026.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,215 hectares (12.2 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Phrao (1,223 ha, 1.0 %).
What was the weather like?
During the fire the temperature reached 35.9 °C, humidity dropped to 29 % and gusts hit 36 km/h. The fire danger index (FWI) reached 33, class High.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Thailand (geoBoundaries). It is not an official report.

Where to verify it

A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.

Emergency number: 199 · 191 · Emergency number and official warnings ›

Satellite cross-check

History of this page · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 17 April 2026 → 18 April 2026.

RSS Changes to this page

Does something look wrong on this page?

This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.

Report an error
What do you think is wrong?

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 199 · 191.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 14 April 2026 to 17 April 2026. 10 Suomi-NPP VIIRS detections on those dates.
  • We have not matched this page with any official record.
  • Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
  • Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2025, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

How we build fire pages: methodology ›

Where this data comes from

The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM2 (Creative Commons Attribution 3.0 Intergovernmental Organisations (CC BY 3.0 IGO)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.